What is Battery Wh vs claimed hours?
Watt-hours is real capacity; 'up to 12 hours' is a lab loop.
Short answer
Under 50 Wh in a 15-inch laptop means you carry the charger everywhere.
Battery Wh vs claimed hours when buying a laptop
Watt-hours is real capacity; 'up to 12 hours' is a lab loop.
Why it matters: Wh divided by realistic 8–15 W draw gives you a truer estimate.
Look for: Under 50 Wh in a 15-inch laptop means you carry the charger everywhere.
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